1. Field of the Invention
The invention relates to a gas conversion process in which hydrogen produced from the syngas is used to treat gas well hydrocarbon liquids. More particularly, the invention relates to a process for synthesizing hydrocarbons and producing hydrogen from a syngas feed which is derived from natural gas, with at least a portion of the hydrogen used for hydrodesulfurizing sulfur-containing hydrocarbon liquids recovered from the natural gas.
2. Background of the Invention
Gas conversion processes are known in which a synthesis gas feed comprising a mixture of H.sub.2 and CO is fed into a hydrocarbon synthesis reactor in which it reacts in the presence of a Fischer-Tropsch catalyst under conditions effective to form higher molecular weight hydrocarbons. These processes include fixed bed, fluid bed and slurry hydrocarbon synthesis, all of which are well documented in various technical articles and in patents. In many cases it is desired that the synthesized hydrocarbons comprise mostly C.sub.5+ hydrocarbons (e.g., C.sub.5+ -C.sub.200) and preferably C.sub.10+ hydrocarbons, at least a portion of which are solid at standard conditions of room temperature and pressure. It is preferred in a slurry hydrocarbon synthesis process that the hydrocarbons comprise mostly C.sub.5+ paraffins. These hydrocarbons are upgraded to more valuable products by one or more hydroconversion operations in which at least a portion of the molecular structure is changed by reacting with hydrogen. Hydrogen is also required for rejuvenating the hydrocarbon synthesis catalyst and sometimes for maintaining or changing the H.sub.2 to CO ratio of the synthesis gas feed for the hydrocarbon synthesis. Natural gas comprises primarily methane and is a preferred feed for the synthesis gas generation. In addition to methane, natural gas also contains lessor amounts of valuable, sulfur-containing C.sub.2+ hydrocarbons (e.g., 1-10%), including sulfur-containing hydrocarbon liquids which are separated and recovered from the gas. These hydrocarbon liquids are reacted with hydrogen in the presence of a catalyst to remove the sulfur (hydrodesulfurized).